Phyllospongianes A-E, Dinorscalarane Sesterterpenes from the Marine Sponge .

Phyllospongianes A-E (-), five new scalarane derivatives featuring an unprecedented 6/6/6/5 tetracyclic dinorscalarane scaffold, along with the known probable biogenetic precursor, 12-deacetylscalaradial (), were isolated from the marine sponge . The structures of the isolated compounds were determined by analysis of spectroscopic data and electronic circular dichroism experiments. Compounds - are the first 6/6/6/5 tetracyclic scalarane derivatives to be reported within the scalarane family. Compounds , , and exhibited antibacterial activity against , , , , , , and with MIC values ranging from 1 to 8 μg/mL. Furthermore, compound exhibited significant cytotoxic activity on MDA-MB-231, HepG2, C4-2-ENZ, MCF-7, H460, and HT-29 cancer cell lines with IC values in the range between 0.7 and 13.2 μM.